Yes it is. The School Based Assessment is a mandatory component for in-school candidates. If you are registered to submit an SBA and do not submit this component for the examination, you will be reported “Ungraded – SBA/IA component not received”. An Alternative Paper to SBA (normally referred to as Paper 032) is available to candidates registered at private centres.
Each subject syllabus will outline the components of the various papers. Syllabuses can be accessed via https://www.cxc.org/syllabus-downloads/